After nearly four months, authorities in Philadelphia are ready to prosecute the alleged killer in the shocking murder of teenager Sabriya McLean. The 15-year-old Delaware girl was found dead on November 27, 2017 after meeting up with a man she encountered via Facebook, police said.

The suspect, 23-year-old Cole Swaringer-Herring, allegedly stabbed the victim nearly 80 times after the pair met up in Philadelphia. Swaringer-Herring then set the teen's body on fire, according to news reports.

In the courtroom in in mid-February, Municipal Court Judge Karen Yvette Simmons heard testimony from Swaringer-Herring's former girlfriend.

'He told me that he had killed someone'

Taaysia Jones, 19, said that she lived in the same apartment building as the defendant and they began and sexual relationship. Soon she moved into his apartment, with his mother and brother, she told the court.

She said she was at a hospital when he messaged her on Facebook with a startling confession. "He  told me he stabbed her and set her on fire," Jones told the court. "He said, 'I messed up, I messed up," she said. "He told me that he had killed someone."

The chilling admission also seemed to blame Jones herself, she said. Swaringer-Herring said that he stabbed McLean "because I couldn't do anything to you and I was mad at you."

The heinous nature of the crime has raised suspicions that the suspect may be linked to other investigations, police said.

Last fall, authorities immediately set their suspicions on Swaringer-Herring after discovering social media.

“It was a very violent act so we’re looking at him in connection to some other possible cases that we’ve had,” Police Capt. Jack Ryan said, the Associated Press reports.

Sabriya had been reported missing days earlier, according to TV station WCAU. Swaringer-Herring's parents had left their home, leaving an opportunity for him to commit the crime, police said.

He confessed to them when they returned home, station WPVI reports.

Sabriya's charred remains were discovered Tuesday under some leaves behind Swaringer-Herring’s apartment complex, reports the Associated Press.

 Swaringer-Herring is charged with murder, arson and abuse of a corpse, according to authorities.